Process for continuously feeding separate lengths of sheet materials

ABSTRACT

Sheets of polyvinyl chloride about 5 inches wide and 7,500 feet long are folded into individual containers by a set of feed rolls reciprocating back and forth across the container opening. Each sheet is placed in its container so pulling on one end will draw the sheet linearly therefrom and the other end extends a short distance outside of the container opening. At least two containers are placed adjacent each other and the ends of the sheets are heat fused together so processing equipment begins drawing the sheet from the second container after emptying the first container.

United States Patent [72] Inventors Harold C. Gerwin Fraser; Angelo V. Pugliese, Jr., Mount Clemens, both of Mich. [21] Appl. No. 755,846 [22] Filed Aug. 28, 1968 [45] Patented Sept. 21, 1971 [73] Assignee Ford Motor Company Dearborn, Mich.

[54] PROCESS FOR CONTINUOUSLY FEEDING SEPARATE LENGTHS OF SHEET MATERIALS 4 Claims, 2 Drawing Figs.

[52] U.S.CI 156/157 [51] t B65h 75/02 [56] References Cited UNITED STATES PATENTS 2,398,263 4/1946 Trimbach 89/34 2,459,934 1/1949 Haberlin 89/34 2,751,321 6/1956 Sans..... 156/157 2,870,681 1/1959 Linke 89/34 3,071,503 1/1963 Dubois. 156/157 3,331,719 7/1967 Soloff... 156/157 3,342,817 9/1967 Young 156/157 3,456,445 7/1969 Bentele et al. 239/34 Primary Examiner-Carl D. Quarforth Assistant Examiner-Brooks H. Hunt Attorneys-John R. Faulkner and Glenn S. Arendsen ABSTRACT: Sheets of polyvinyl chloride about 5 inches wide and 7,500 feet long are folded into individual containers by a set of feed rolls reciprocating back and forth across the container opening. Each sheet is placed in its container so pulling on one end will draw the sheet linearly therefrom and the other end extends a short distance outside of the container opening. At least two containers are placed adjacent each other and the ends of the sheets are heat fused together so processing equipment begins drawing the sheet from the second container after emptying the first container.

PROCESS FOR CONTINUOUSLY FEEDING SEPARATE LENGTHS OF SHEET MATERIALS SUMMARY OF THE lNVENTlON.

Polyvinyl chloride sheet material intended for use in the production of knitted vinyl described in US. Pat. application Burnett et al. Ser. No. 717,554 filed Apr. 1, 1968 and now US. Pat. No. 3,491,560 is produced in the form of rolls containing about 7,500 linear feet of sheet material about 5 inches wide. Each roll contains enough sheet material to operate a knitting machine for about 45 minutes; when a roll is exhausted the knitting machine must be stopped for about minutes to permit splicing another roll to the trailing end of the previous roll. Down time occasioned by such splicing seriously disrupts the knitting operation and adds significantly to the production costs of the knitted vinyl. Similar difficulties are encountered in processing other sheet materials including woven or knitted goods.

This invention provides a process for continuously feeding separate lengths of sheet materials to processing equipment and thereby eliminates the down time occasioned by stopping the equipment to splice succeeding lengths of material together. The process comprises placing at least two of the lengths of material into separate containers so each length can be removed linearly from its container by a pulling force exerted on the leading end of the length. The trailing end of the length is made accessible from outside of the container by extending the trailing end over one container edge, for example. While the processing equipment is drawing the sheet material from the first container, the leading end of the length in the second container is fastened to the trailing end of the length in the first container. When the first container has been emptied, the processing equipment automatically begins drawing material from the second container. The first container is then moved away from the equipment and filled with another length of material, which is spliced to the trailing end of the material in the second container. These steps are repeated so the processing equipment can be operated continuously.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is an elevation showing schematically a container and the equipment placing a length of sheet material from a roll into the container.

FIG. 2 shows three containers associated with the slitter of the knittcd-vinyl-processing equipment described in the above-mentioned patent application. The slitter has almost emptied the first container and the sheet materials in the second and third containers have been spliced to the trailing edges of the sheet materials in the first and second containers respectively.

DETAILED DESCRIPTION Referring to FIG. 1, a polyvinyl chloride sheet material prepared according to the process described in the above Burnett et al. patent application is wound on a roll 10. The sheet material preferably is made of a polyvinyl chloride resin having an inherent viscosity between 1.28 and 1.35 as described in the Burnett et al. application, the entire disclosure of which is incorporated herein. Each roll is about 5 inches wide and contains about 7,500 linear feet of sheet material.

An open metal container 12 is positioned beneath equipment having a set 13 of rotating feed rolls 14 and 15. Set 13 is capable of reciprocating motion as indicated by the arrow 16 while feed rolls 14 and are rotating. Such equipment can be purchased from the Rhee Industries Division of Rohm and Haas Company Warren, Rhode Island. Container 12 has essentially square comers and is about 30 inches high, 50 inches long, and 9 inches wide. Narrow ledges l7 and 18 extend across the width of the container opening at its leading and trailing edges, respectively. Ledges l7 and 18 project outward from the container opening for a short distance. The interior of the container has a smooth finish free of any sharp protrusions. Pads 20 and 22 of an insulating material such as asbestos can be bonded to the upper sides of the respective ledges.

The set 13 of feed rolls is adjusted to reciprocate back and forth across the lengthwise opening of container 12. Sheet material from roll 10 is placed into container 12 by threading it between rolls 14 and 15, which are located initially near the trailing ledge 18. The leading end 24 of the sheet material from roll 10 is placed on top of pad 22 and the material is draped down the side of container 12. Rolls 14 and 15 then begin moving toward the front edge of container 12 and at the same time begin rotating to distribute a portion 26 of the sheet material across the bottom of the container. The rolls reverse direction upon reaching the front end of container 12 and thus fold a second portion 28 of the sheet material back across the top of the first portion. In this manner rolls 14 and 15 produce successive folds of sheet material in the container. The folds are permitted to slide laterally relative to each other until the entire area of the container is covered thereby.

When roll 10 has been exhausted, its trailing end 30 is placed on top of pad 20 as shown in phantom in FIG. 1. It is preferable that rolls 14 feed the sheet material into the container at a rate exceeding that necessary for producing flat folds so small ripples indicated by numeral 32 are produced in each of the folds; such ripples prevent the folds from sticking to each other under the weight of succeeding material. Note that the leading end 24 from the roll becomes the trailing end in the container and the trailing end from the roll becomes the leading end in the container.

Turning to FIG. 2, the drive rolls 34 and 36 of a slittingknitting machine such as that shown in the Burnett et al. application are mounted at approximately twice the height of container 12 above the floor. Drive rolls 34 and 36 are positioned adjacent the upper and lower arbors 38 and 40 of the slitting mechanism.

Container 12 filled with sheet material in the manner described above is positioned below drive rolls 34 and 36 and end 30 of the material in the container is fed through the drive rolls and the arbors of the slitting mechanism. A container 12' similar in all respects to container 12 and filled with sheet material in the same manner is positioned adjacent container 12 with the leading edge 17' of container 12 abutting the trailing edge 18 of container 12. Similarly, a third container 12" is positioned adjacent container 12 with the leading edge 17" abutting the trailing edge 18.

While sheet material is being drawn from container 12 by rolls 34 and 36, end 24 of the sheet material in container 12 is spliced to end 30' of the sheet material in container 12' and end 24 of the material in container 12 is spliced to end 30" of the material in container 12''. Such splicing preferably is carried out by heating the end and fusing the ends together in any conventional heat-sealing manner. The presence of pads 20 and 22 permits heating on the working surfaces formed by abutting ledges l7 and 18 without excessive heat reaching the sheet material in the containers.

When rolls 34 and 36 have emptied container 12, the rolls automatically begin drawing material from container 12'. Container 12 then can be moved away from the slitting equipment and containers 12' and 12" moved forward into the positions shown for containers l2 and 12', respectively.

Thus, this invention provides a process for feeding continuously finite lengths of sheet material to processing equipment. The containers can be made of materials other than metal and container height and length can be modified within wide limits. Container width also can be increased and lateral movement of the folds can be induced so each container will hold more than one roll of material. In this technique the rolls for each container are spliced together during the filling step. Down time of subsequent processing equipment previously necessary for connecting new lengths of material can be eliminated completely by the process.

We claim:

l. A process for continuously supplying separate lengths of thermoplastic polymeric sheet materials to continuous processing equipment comprising:

feeding at least two of said lengths into separate containers so succeeding portions of each'length fold across preceding portions of the length and so each length can be removed linearly from its container by pulling force exerted by the processing equipment on the leading end of the length, each of said containers having an outwardly projecting ledge at the approximate level of the container opening, said feeding step occurring at a rate exceeding that necessary to produce flat succeeding portions so small ripples are produced in each folded portion, said feeding step being conducted so the trailing end of the length is accessible from outside of the container,

locating the containers adjacent each other and using the projecting ledge as a working surface to bond the leading end of the second length to the trailing end of the first length so the processing equipment begins drawing the second length from its container when the first length has been withdrawn from its container.

2. The process of claim 1 in which each container has an outwardly projecting ledge at the approximate level of the container opening on both the front and rear edges, and comprising locating at least two containers adjacent each other with the ledge at the trailing edge of the first container abutting the ledge at the leading edge of the second container to form a working surface, and using said working surface to fasten the leading end of the second length of material to the trailing end of the first length.

3. The process of claim 2 in which the ends of the lengths are fastened by heating the ends and fusing the ends together.

4. The process of claim 1 in which each length is placed into its container so its trailing end extends over the trailing edge of its container. 

2. The process of claim 1 in which each container has an outwardly projecting ledge at the approximate level of the container opening on both the front and rear edges, and comprising locating at least two containers adjacent each other with the ledge at the trailing edge of the first container abutting the ledge at the leading edge of the second container to form a working surface, and using said working surface to fasten the leading end of the second length of material to the trailing end of the first length.
 3. The process of claim 2 in which the ends of the lengths are fastened by heating the ends and fusing the ends together.
 4. The process of claim 1 in which each length is placed into its container so its trailing end extends over the trailing edge of its container. 